The main theoretical objective of this proposal is to understand the relationships between particular types of family household structures and the demographic transition in Europe during the past two centuries. On the assumption that there were pathways to demographic modernity in Europe which led through different types of family configuration research will concentrate on three areas the premodern populations of which lived in extended family households. The populations of the Aland Islands (Finland), Latvia, and Serbia (Yugoslavia) will be investigated at various points in time from the early eighteenth century onward by means of computer analysis of household lists and other pertinent demographic information. At each point, the extended family household will be investigated with respect to its social and kinship structures, developmental cycle, and the associated economic, class, and ecological influences which brought it into being or were reshaping it. The extended family household will be conceived as an area for decisions on marriage, post-marital residence, childbirth and child-rearing, and other matters contributing to prevailing fertility levels. Attention will be focused on the concurrent decline in fertility levels and the modification of household structure in an effort to establish links between the two phenomena. The project involves a social-cultural anthropologist, a social biologist, a social historian, and a European ethnologist who will collaborate in analyzing the data from each area and in the comparative analysis.